While cellular telephone networks and wireless local area networks (LANs) provide ready access to global communication networks from cities, suburbs and even rural areas in the developed world, there are still vast areas of the world where access to communication via the aforementioned wireless communications or via regular telephone networks is not available. In such instances communications via satellites is a viable option. Satellite communications can be useful to a variety of civilian and military users. Certain communication satellites systems use directional antennas that cover a limited geographic region. For people who travel extensively it would be desirable to have portable wireless communication devices that are able to communicate using multiple communication systems e.g., terrestrial cellular systems and satellites.
Additionally different types of communication services may be available in the same geographic from different sources (e.g., satellites, radio towers) and using different frequency bands. In order for the portable communication device to utilize each source it must include an antenna that exhibits the appropriate frequency response and has a gain pattern consistent with the frequency and the location of the source with which it is communing. For example while a gain pattern that is strong at relatively low zenith angles, is appropriate for communicating with overhead satellites, a gain pattern that is stronger at somewhat higher zenith angles may be more suitable for exchanging signals with a terrestrial antenna. Adding multiple antennas to a portable (e.g., handheld) device to handle multiple needs can lead to an excessively bulky and unwieldy device. Furthermore multiple antennas could interfere with each other.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.